Satellite photos suggest Pakistan is expanding nuclear capability

PAKISTAN has begun building what independent analysts say is a powerful new reactor for producing plutonium, a move that, if verified, would signal a big expansion of its nuclear weapons capabilities and a potential escalation in the region's arms race.

Satellite photos of the Khushab nuclear site show what appears to be a partially completed heavy-water reactor capable of producing enough plutonium for 40 to 50 nuclear weapons a year, a twentyfold increase from Pakistan's current capabilities, a technical assessment by Washington-based nuclear experts says.

The construction site is next to Pakistan's only plutonium production reactor, a 50-megawatt unit that began operating in 1998. The dimensions of the new reactor suggest a capacity of 1000 megawatts or more, the Institute for Science and International Security says. Pakistan is believed to have 30 to 50 uranium warheads, which tend to be heavier and more difficult than plutonium warheads to mount on missiles.

"South Asia may be heading for a nuclear arms race that could lead to arsenals growing into the hundreds of nuclear weapons, or at minimum, vastly expanded stockpiles of military fissile material," David Albright and Paul Brannan concluded in the institute's technical assessment.

The assessment's key judgements were endorsed by two other independent nuclear experts who reviewed the commercially available satellite images, provided by Digital Globe, and supporting data. In Pakistan, officials would not formally confirm or deny the report, but a senior Pakistani official, speaking on condition of anonymity, acknowledged a nuclear expansion was under way.

"Pakistan's nuclear program has matured. We're now consolidating the program with further expansions," the official said.

The expanded program includes "some civilian nuclear power and some military components", he said.

The development raises fresh concerns about a decades-old rivalry between Pakistan and India. Both countries possess dozens of nuclear warheads and a variety of missiles and other means for delivering them.

Pakistan, like India, has never signed the nuclear non-proliferation treaty. One of its pioneering nuclear scientists, Abdul Qadeer Khan, confessed two years ago to operating a network that supplied nuclear materials and expertise to Libya, Iran and North Korea.

The evidence of a possible escalation comes as Congress prepares to debate a controversial nuclear co-operation agreement between the Bush Administration and India. The agreement would grant India access to sensitive US nuclear technology in return for placing its civilian nuclear reactors under tighter safeguards. No such restrictions were placed on India's military nuclear facilities.

India has an estimated 30 to 35 nuclear warheads based on a sophisticated plutonium design. Pakistan, which uses a simpler, uranium-based warhead design, has sought for years to modernise its arsenal, and a new heavy-water reactor could allow it to do so, weapons experts say.

"With plutonium bombs, Pakistan can fully join the nuclear club," said a Europe-based diplomat and nuclear expert after reviewing the satellite evidence. He concurred with the institute assessment but offered a lower estimate - "up to tenfold" - for the increase in Pakistan's plutonium production. A US-based expert agreed fully with the institute's estimates.

Pakistan began its nuclear program in the early 1970s. Construction of the larger reactor at Khushab apparently began some time in 2000. Satellite photos taken in early 2005 showed the frame of a rectangular building enclosing what appeared to be the round metal shell of a large nuclear reactor. Satellite photos taken a year later show the roof of the structure still incomplete, allowing an unobstructed view of the reactor's features.

After comparing a sequence of satellite photos, the institute analysts estimated that the new reactor was "a few years" from completion.